The invention relates to a telescoping wand for a vacuum cleaner, including an inner suction pipe slidably arranged in an outer suction pipe to allow a telescoping adjustment thereof, and a variably extendable electrical cord or cable to allow electrically powered accessories, such as an electric carpet beater brush, to be connected to the telescoping wand and receive electrically power directly therefrom.
It is commonly known to provide various accessories that can be connected to an extension wand or floor wand of a vacuum cleaner, and to provide such accessories with electrical power through an electrical cord or cable that is connected to or incorporated in the wand. One known arrangement involves simply securing an electrical cable somewhat loosely on the outside of the vacuum hose and the extension wand. Such an arrangement is neither very functional nor aesthetically satisfactory.
It is further known to provide two-part telescoping vacuum wands, which are telescopably adjustable in length, to provide a comfortable height or extension length for the particular user of the vacuum cleaner. An electrical cable may be incorporated into such telescoping wands in various conventional manners. In one known arrangement, a tubular chamber is provided running parallel to the vacuum pipe of the telescoping wand, whereby this tubular chamber is also embodied in a telescoping manner and houses an extendable spiral cord or cable. In another known arrangement, a flat chamber is provided on the outside of the vacuum pipe of the telescoping wand, and a flexible electrical cord or cable is guided over a spring-loaded pulley arrangement or block-and-tackle arrangement, whereby the cable is pulled out of this mechanism along with the telescoping extension of the wand. Such an arrangement is disclosed, for example, in German Patent Publication DE 195 35 493 A1.
In practice it has been found that the known arrangements of a variably extendable electrical cord for a telescopably extendable vacuum wand are rather complicated and costly to manufacture, rather prone to failure and thus requiring maintenance and repair during the operating life of the vacuum cleaner, and also require a relatively large space, giving the complete wand arrangement a bulky configuration and appearance.
In view of the above, it is an object of the invention to provide a simplified arrangement of a length-adjustable, adaptable, compact, and functionally robust and reliable electrical connection for supplying electrical power to accessory devices connected to the end of a telescoping extension wand of a vacuum cleaner. It is a further object of the invention to provide such an arrangement that has relatively small dimensions to extend unobtrusively along the telescoping wand. Yet another object is to ensure that such an arrangement meets all international standards relating to the required electrical insulation and reliability. The invention further aims to avoid or overcome the disadvantages of the prior art, and to achieve additional advantages, as apparent from the present specification.
The above objects have been achieved according to the invention in a telescoping vacuum wand arrangement for a vacuum cleaner, including an inner vacuum pipe slidingly arranged within an outer vacuum pipe, a magazine chamber or cord reserve storage chamber running lengthwise along the outer vacuum pipe, a cord receiver element that is coupled to the inner vacuum pipe and slidable into and out of the magazine chamber, a slider that is longitudinally slidably arranged and guided within the magazine chamber, and an electrical cable or cord. The cord is fixed to the inner vacuum pipe at a first end of the wand, and from there is received and extends along the cord receiver element into the magazine chamber. At an end of the receiver element within the magazine chamber, the cord forms a first fixed loop that is fixed to the cord receiver element. From there, the cord runs back along the receiver element and particularly between the receiver element and the slider that is slidably guided parallel to the receiver element, to a cord guide opening of the slider. There, the cord forms a second movable or unfixed loop that passes through the cord guide opening, e.g. a hole in the slider or an end guide of the slider. From there, the cord extends along the opposite side of the slider to a fixed end of the cord at a second end of the telescoping wand. In this manner, the cord zig-zags back-and-forth in two opposite directions parallel to the longitudinal axis of the wand, to form a general Z- or S-shape of the cord (called a xe2x80x9cmeandering shapexe2x80x9d herein) within the magazine chamber, more particularly as follows.
With the above arrangement according to the invention, the cord receiver element slidably moves indirectly with the inner vacuum pipe and thereby carries out a telescoping motion relative to the magazine chamber, together with the telescoping motion of the inner vacuum pipe relative to the outer vacuum pipe. The cord forms a U-shaped loop that is fixed or secured to the free end of the cord receiver element protruding into the magazine chamber, and the cord is also fixed or secured at the second end of the wand. Between these secured points, the cord meanders in the form of another U-shaped loop over or through a guide of the slider. This back and forth meandering or looping of the cord provides an adjustable length reserve or supply of the electrical cord, of which the longitudinal extension length depends on the relative positions and relative overlap of the slider and the cord receiver element. Thereby, the cord length is adaptable to different telescoping length adjustments of the telescopable vacuum wand.
Suitable electrical connectors, couplers, or contact receivers are provided respectively at the ends of the inner vacuum pipe and the outer vacuum pipe, to allow the electrical cord to be connected to a desired accessory device on the one hand, and to a source of electrical power, for example preferably provided through an electrified vacuum hose from the vacuum cleaner itself, on the other hand.
A first cord guide channel is formed between the slider and the cord receiver element, while a second cord guide channel is formed on the opposite side of the slider, between the slider and a side wall of the magazine chamber. The cord is respectively guided in these guide channels on opposite sides of the slider. The guide channels are properly dimensioned, so that the cord is guided and supported while slidingly shifting therein in a kink-free manner. Moreover, preferably, the dimensions are such that the sliding displacement of the cord receiver element slidingly pulls and pushes the cord (depending on the direction of motion of the cord receiver element relative to the magazine chamber), and thereby correspondingly transmits a tension-pulling force and a thrust-pushing force through the cord (especially through the movable second cord loop) onto the slider. As a result, this causes the slider to slidingly move within the magazine chamber as the cord receiver element is extended from or retracted into the magazine chamber.
In the above manner, no other mechanisms are required for properly moving the slider. Alternatively, a tension spring or compression spring may slidingly bias the slider to urge the slider toward the first end of the telescoping wand. As mentioned above, however, in the preferred simplest embodiment, such a biasing spring or other biasing means can be completely omitted due to the pushing and pulling sliding force being transmitted from the cord receiver element through the cord to the slider. This force transmission is especially provided through the movable second cord loop passing through (and bearing against) the cord guide opening of the slider, but may additionally include a force transmission component that is transmitted frictionally by the cord rubbing along the side of the slider facing the cord receiver element.
In this manner, the invention achieves a very simple, robust and reliable arrangement of a freely length-adjustable or adaptable electrical cord, with a relatively compact length and width dimension. Moreover, the electrical cord is stored in a back-and-forth looping fashion and is thereby positively guided in a block-and-tackle type arrangement and motion for achieving a required length adjustment, without needing any special means for moving the various components or the like. Namely, with the simple freely-sliding slider and the cord receiver element, the invention avoids the need for plural block-and-tackle elements and their suitable coupling to each other that would otherwise typically be needed for a block-and-tackle arrangement. The above mentioned sliding force initiated by the cord receiver element is all that is needed to appropriately slide the slider, particularly so that the slider is correspondingly displaced by one half the sliding distance of the cord receiver element to maintain the cord in a kink-free looped arrangement while adjusting its extended length as needed.
An advantageous embodiment of the cord receiver element is in the form of a linear sleeve or sheath tube in which the cord is received. Alternatively, the cord receiver element may comprise a linearly extending sectional profile member that is open along at least one side thereof, e.g. in the form of a C-section member or the like.
In order to increase the sliding security of the respective portions or strands of the electrical cord on the opposite sides of the slider, while maintaining a kink-free sliding support thereof, the inventive arrangement preferably provides guide channels that are bounded and enclosed on all sides thereof. In a simple embodiment of this feature, the bounding walls of the guide channels are formed directly by a floor and cover, and/or side walls, of the magazine chamber. The slider itself also acts as a divider or bounding wall between the two guide channels.
The preferred simplest embodiment of the slider is in the form of a flat slider, namely a flat plate-shaped slider element that is slidingly received and guided along guide tracks or grooves at least along its longitudinal edges on its height axis, i.e. its width dimension, along the floor and cover of the magazine chamber. Correspondingly, the electrical cord is preferably a flat cord arranged with its width dimension or height axis lying approximately parallel to that of the flat slider.
To prevent the electrical cord from kinking or forming an enlarged uncontrollably variable loop at the end of the cord receiver element, i.e. sheath tube, when the sheath tube is slidingly inserted into and extended from the magazine chamber, the first loop of the electrical cord is preferably fixed directly at the end of the sheath tube where the cord exits from the tube into the magazine chamber. This is preferably achieved by a retaining or fixing element such as a cord fixing clip directly on the end of the sheath tube. This cord fixing clip especially forms and retains the loop configuration or bend of the first fixed loop of the cord.
An advantageous embodiment of the magazine chamber involves integrating the magazine chamber directly onto the outer wall of the outer vacuum pipe. Namely, the outer wall of the outer vacuum pipe will then form the floor of the magazine chamber, which is integrally formed as a single component with the pipe. Alternatively, the magazine chamber may be a separate component that is mountable onto the outer vacuum pipe by means of any suitable mounting elements, e.g. screws, rivets, clips, plastic or metal welds, adhesive bonds, etc. In this manner, the magazine chamber may even be retrofitted onto previously existing telescoping vacuum wands.